This invention relates to an apparatus for cleaning a tubular member, and in particular, to a cleaning nozzle for a condenser tube.
This invention will generally be described in connection with tube cleaners for heat exchanger and condenser tubes. However, it is to be appreciated that the invention has application to a wide variety of tubes and that the scope of the invention is not limited to such cleaners.
Heat exchangers and condensers often contain a large number of metal tubes through which heat exchanging fluid flows. The tubes are usually arrayed in parallelism and are supported adjacent their ends by transverse tube sheets. Over time, the tube sheets become heavily pitted, corroded or worn away, thus weakening the entire structure. To prevent this, various coatings are applied to the tube sheets, thereby preventing or substantially retarding pitting, corrosion and wear on the tube sheets.
It is well known that the operating efficiency of heat exchangers and condensers is reduced and fluid flow is restricted when the condenser tubes become fouled by such deposits as scale, algae, mud, slime and the like. In addition, if the tubes are not cleaned regularly, deposits may cause pitting or corrosion of the tubes, resulting in major damage and shortened tube life.
The interior of tube members such as a heat exchanger tube are generally cleaned by forcing a pressurized cleaning medium, e.g., pressurized gas/particulate solid mixture, water, water/solid slurry, etc., through the tubular member. In the prior art, tube cleaning generally involved the insertion of brass nozzles into a tube and subjecting the tube interior to high pressure from compressed air or water. However, it has been determined that the use of metallic nozzles damages the tube sheet coatings about the tube end. As a result, the prior art now generally uses nylon nozzles. However, this still puts pressure on the coating about the tube ends and damaging the coating. Because nylon nozzles are soft, they do not work well under high pressure uses.
All existing tube cleaning nozzles are conical in shape and made from metal of plastic. The existing nozzles contact the tube sheet coating when placed in the tube. This contact frequently results in damage to the tube sheet coating.
The present invention addresses the limitations of prior art devices by providing a nozzle which is cushioned with soft washers. The present invention provides a stiffened nozzle adapted to handling high pressure, while at the same time providing cushioning at all contact points on the tube sheet and within the tube being cleaned.
These together with other objects of the invention, along with various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of the invention.